<properties>
  <maven.compiler.source>8</maven.compiler.source>
  <maven.compiler.target>8</maven.compiler.target>
</properties>

<dependencies>
  <!-- https://mvnrepository.com/artifact/org.apache.httpcomponents/httpclient -->
  <dependency>
    <groupId>org.apache.httpcomponents</groupId>
    <artifactId>httpclient</artifactId>
    <version>4.5.13</version>
  </dependency>
  <!-- https://mvnrepository.com/artifact/org.json/json -->
  <dependency>
    <groupId>org.json</groupId>
    <artifactId>json</artifactId>
    <version>20220320</version>
  </dependency>
</dependencies>

public class TestMain {

	private static final String ONELOGIN_SUBDOMAIN = "deringo-dev";
	
	// OneLogin Administration -> Applications -> select Application, get ID from URL
	private static final String ONELOGIN_APP_ID = "1739301";
	
	// OneLogin Administration -> Developers -> API Credentials
	private static final String ONELOGIN_CLIENT_ID = "12345<geheim>67890";
	private static final String ONELOGIN_CLIENT_SECRET = "12345<geheim>67890";
	
	
	public static void main(String[] args) {
		TestMain main = new TestMain();

		main.sayHello();
	}

	private void sayHello() {
		System.out.println("Hello World!");
	}
}

private String getAccessToken() {

  CloseableHttpClient client = HttpClientBuilder.create().build();

  HttpPost request = new HttpPost(String.format("https://%%s.onelogin.com/auth/oauth2/v2/token", ONELOGIN_SUBDOMAIN));

  String credentials = String.format("%%s:%%s", ONELOGIN_CLIENT_ID, ONELOGIN_CLIENT_SECRET);
  byte[] encodedAuth = Base64.getEncoder().encode(credentials.getBytes());
  String authHeader = "Basic " + new String(encodedAuth);

  request.setHeader("Authorization", authHeader);
  request.addHeader("Content-Type", "application/json");
  request.setEntity(new StringEntity("{ \"grant_type\": \"client_credentials\" }", "UTF-8"));

  try {
    CloseableHttpResponse reponse = client.execute(request);

    String content = EntityUtils.toString(reponse.getEntity());

    JSONObject json = new JSONObject(content);

    String accessToken = json.getString("access_token");
    return accessToken;

  } catch (IOException e) {
    e.printStackTrace();
    return null;
  }
}

private void listAppUsers() {
  String resourceURL = String.format("https://%%s.onelogin.com/api/2/apps/%%s/users", ONELOGIN_SUBDOMAIN, ONELOGIN_APP_ID);

  CloseableHttpClient client = HttpClientBuilder.create().build();

  HttpGet request = new HttpGet(resourceURL);
  request.setHeader("Authorization", "bearer " + getAccessToken());
  request.addHeader("Content-Type", "application/json");

  try {
    CloseableHttpResponse reponse = client.execute(request);

    String content = EntityUtils.toString(reponse.getEntity());

    JSONArray jsonArray = new JSONArray(content);
    jsonArray.forEach(o -> System.out.println(o));

  } catch (IOException e) {
    e.printStackTrace();
  }
}

private void listRoles() {
  String resourceURL = String.format("https://%%s.onelogin.com/api/2/roles", ONELOGIN_SUBDOMAIN);

  CloseableHttpClient client = HttpClientBuilder.create().build();

  HttpGet request = new HttpGet(resourceURL);
  request.setHeader("Authorization", "bearer " + getAccessToken());
  request.addHeader("Content-Type", "application/json");

  try {
    CloseableHttpResponse reponse = client.execute(request);

    String content = EntityUtils.toString(reponse.getEntity());

    JSONArray jsonArray = new JSONArray(content);
    jsonArray.forEach(o -> System.out.println(o));

  } catch (IOException e) {
    e.printStackTrace();
  }
}

String resourceURL = String.format("https://%%s.onelogin.com/api/2/roles?app_id=%%s&name=u", ONELOGIN_SUBDOMAIN, ONELOGIN_APP_ID);

String queryParameter = "";
String resourceURL = String.format("https://%%s.onelogin.com/api/2/apps/%%s/users%%s", ONELOGIN_SUBDOMAIN, ONELOGIN_APP_ID, queryParameter);

String queryParameter = "?fields=firstname,lastname";

String queryParameter = "?lastname=Mustermann";

// funktioniert NICHT:
String queryParameter = "?lastname=Mustermann,firstname=Erika";

// funktioniert NICHT:
String queryParameter = "?lastname=Mustermann&firstname=Erika";

String queryParameter = "?lastname=Muster*&firstname=Erika&fields=firstname,lastname";

String queryParameter = "?page=1&limit=1&sort=-lastname";

// erster Aufruf:
String queryParameter = "?page=1&limit=1";
[...]
String afterCursor = response.getFirstHeader("After-Cursor").getValue();
[...]

// zweiter Aufruf
queryParameter = "?cursor=" + afterCursor;

private void createUser() throws Exception {
  String resourceURL = String.format("https://%%s.onelogin.com/api/2/users", ONELOGIN_SUBDOMAIN);

  CloseableHttpClient client = HttpClientBuilder.create().build();

  HttpPost request = new HttpPost(resourceURL);
  request.setHeader("Authorization", "bearer " + getAccessToken());
  request.addHeader("Content-Type", "application/json");

  String json = "{\"username\":\"min.requirements\"}";
  StringEntity entity = new StringEntity(json);
  request.setEntity(entity);

  try {
    CloseableHttpResponse response = client.execute(request);
    System.out.println(response.getStatusLine());
    String content = EntityUtils.toString(response.getEntity());
    System.out.println(content);
    JSONObject o = new JSONObject(content);
    System.out.println("new User ID: " + o.get("id"));
  } catch (IOException e) {
    e.printStackTrace();
  }
}

HTTP/1.1 201 Created
{"firstname":null,"updated_at":"2022-06-01T14:34:52.423Z","role_ids":[],"invitation_sent_at":null,"member_of":null,"distinguished_name":null,"email":null,"id":178924216,"password_changed_at":null,"manager_ad_id":null,"group_id":null,"invalid_login_attempts":0,"phone":null,"title":null,"preferred_locale_code":null,"department":null,"samaccountname":null,"lastname":null,"custom_attributes":{"my_role":null},"created_at":"2022-06-01T14:34:52.423Z","directory_id":null,"locked_until":null,"status":7,"company":null,"activated_at":null,"last_login":null,"trusted_idp_id":null,"manager_user_id":null,"username":"min.requirements","comment":null,"external_id":null,"state":1,"userprincipalname":null}
new User ID: 178924216

private void createUser() throws Exception {
  String resourceURL = String.format("https://%%s.onelogin.com/api/2/users", ONELOGIN_SUBDOMAIN);

  CloseableHttpClient client = HttpClientBuilder.create().build();

  HttpPost request = new HttpPost(resourceURL);
  request.setHeader("Authorization", "bearer " + getAccessToken());
  request.addHeader("Content-Type", "application/json");

  JSONObject json = new JSONObject()
    .put("firstname", "Happy")
    .put("lastname", "Gilmore")
    .put("username", "happy.gilmore")
    .put("password", "helloworld123")
    .put("password_confirmation", "helloworld123");
  StringEntity entity = new StringEntity(json.toString());
  request.setEntity(entity);

  try {
    CloseableHttpResponse response = client.execute(request);
    System.out.println(response.getStatusLine());
    String content = EntityUtils.toString(response.getEntity());
    System.out.println(content);
    JSONObject o = new JSONObject(content);
    System.out.println("new User ID: " + o.get("id"));
  } catch (IOException e) {
    e.printStackTrace();
  }
}

HTTP/1.1 201 Created
{"firstname":"Happy","updated_at":"2022-06-01T14:43:30.646Z","role_ids":[],"invitation_sent_at":null,"member_of":null,"distinguished_name":null,"email":null,"id":178924824,"password_changed_at":"2022-06-01T14:43:30.629Z","manager_ad_id":null,"group_id":null,"invalid_login_attempts":0,"phone":null,"title":null,"preferred_locale_code":null,"department":null,"samaccountname":null,"lastname":"Gilmore","custom_attributes":{"my_role":null},"created_at":"2022-06-01T14:43:30.646Z","directory_id":null,"locked_until":null,"status":1,"company":null,"activated_at":"2022-06-01T14:43:30.644Z","last_login":null,"trusted_idp_id":null,"manager_user_id":null,"username":"happy.gilmore","comment":null,"external_id":null,"state":1,"userprincipalname":null}
new User ID: 178924824

private void updateUser(Integer id) throws Exception {
  String resourceURL = String.format("https://%%s.onelogin.com/api/2/users/%%d", ONELOGIN_SUBDOMAIN, id);

  CloseableHttpClient client = HttpClientBuilder.create().build();

  HttpPut request = new HttpPut(resourceURL);
  request.setHeader("Authorization", "bearer " + getAccessToken());
  request.addHeader("Content-Type", "application/json");

  JSONObject json = new JSONObject()
    .put("firstname", "Very Happy");
  StringEntity entity = new StringEntity(json.toString());
  request.setEntity(entity);

  try {
    CloseableHttpResponse response = client.execute(request);
    System.out.println(response.getStatusLine());
    String content = EntityUtils.toString(response.getEntity());
    System.out.println(content);
    JSONObject o = new JSONObject(content);
    System.out.println("User ID: " + o.get("id"));
    System.out.println("Firstname: " + o.get("firstname"));
  } catch (IOException e) {
    e.printStackTrace();
  }
}

HTTP/1.1 200 OK
{"firstname":"Very Happy","state":1,"manager_user_id":null,"department":null,"comment":null,"created_at":"2022-06-01T14:43:30.646Z","email":null,"last_login":"2022-06-01T14:46:10.795Z","lastname":"Gilmore","activated_at":"2022-06-01T14:43:30.644Z","directory_id":null,"updated_at":"2022-06-01T14:57:22.656Z","group_id":null,"samaccountname":null,"status":1,"userprincipalname":null,"trusted_idp_id":null,"title":null,"manager_ad_id":null,"invalid_login_attempts":0,"locked_until":null,"phone":null,"role_ids":[],"invitation_sent_at":null,"company":null,"distinguished_name":null,"external_id":null,"password_changed_at":"2022-06-01T14:43:30.629Z","preferred_locale_code":null,"id":178924824,"member_of":null,"username":"happy.gilmore","custom_attributes":{"my_role":null}}
User ID: 178924824
Firstname: Very Happy

private void addUserToRole(Integer roleId, Integer userId) throws Exception {
  String resourceURL = String.format("https://%%s.onelogin.com/api/2/roles/%%d/users", ONELOGIN_SUBDOMAIN, roleId);

  CloseableHttpClient client = HttpClientBuilder.create().build();

  HttpPost request = new HttpPost(resourceURL);
  request.setHeader("Authorization", "bearer " + getAccessToken());
  request.addHeader("Content-Type", "application/json");

  StringEntity entity = new StringEntity("[" + userId + "]");
  request.setEntity(entity);

  try {
    CloseableHttpResponse response = client.execute(request);
    System.out.println(response.getStatusLine());
    String content = EntityUtils.toString(response.getEntity());
    System.out.println(content);
  } catch (IOException e) {
    e.printStackTrace();
  }
}

HTTP/1.1 200 OK
[{"id":178924824}

private void removeUserFromRole(Integer roleId, Integer userId) throws Exception {
  String resourceURL = String.format("https://%%s.onelogin.com/api/2/roles/%%d/users", ONELOGIN_SUBDOMAIN, roleId);

  CloseableHttpClient client = HttpClientBuilder.create().build();

  HttpPost request = new HttpPost(resourceURL) {
    @Override
    public String getMethod() {
      return "DELETE";
    }
  };
  request.setHeader("Authorization", "bearer " + getAccessToken());
  request.addHeader("Content-Type", "application/json");

  StringEntity entity = new StringEntity("[" + userId + "]");
  request.setEntity(entity);

  try {
    CloseableHttpResponse response = client.execute(request);
    System.out.println(response.getStatusLine());
  } catch (IOException e) {
    e.printStackTrace();
  }
}

HTTP/1.1 204 No Content

HttpPost request = new HttpPost(resourceURL) {
  @Override
  public String getMethod() {
    return "DELETE";
  }
};
[...]
request.setEntity(entity);

private void deleteUser(Integer userId) throws Exception {
  String resourceURL = String.format("https://%%s.onelogin.com/api/2/users/%%d", ONELOGIN_SUBDOMAIN, userId);

  CloseableHttpClient client = HttpClientBuilder.create().build();

  HttpDelete request = new HttpDelete(resourceURL);
  request.setHeader("Authorization", "bearer " + getAccessToken());
  request.addHeader("Content-Type", "application/json");

  try {
    CloseableHttpResponse response = client.execute(request);
    System.out.println(response.getStatusLine());
  } catch (IOException e) {
    e.printStackTrace();
  }
}

HTTP/1.1 204 No Content